Primary- combustion- or explosion-device for internal combustion engines



F. MARBURG ,939,180

FOR INTERNAL COMBUSTION ENGINES Dec. 12, 1933.

PRIMARY 00 Filed June 18, 1929 4 Sheets-Sheet. l

R O T N E V m F. MARBURG Dec. 12, 1933.

PRIMARY COMBUSTION 0R EXPLOSION DEVICE FOR INTERNAL COMBUSTION ENGINES 4 Sheets-Sheet 2 Filed June 18, 1929 INVENTOR F. MARBURG Dec. 12, 1933.

PRIMARY COMBUSTION OR EXPLOSION DEVICE FOR INTERNAL COMBUSTION ENGINES 4 Sheets-Sheet 3 Filed June 18, 1929 R O T N E V m Dec. 12, 1933. F. MARBURG 1,939,180

PRIMARY COHBUSTI N OR EXPLOSION DEVICE FOR Filed June 18, 1929 4 Sheets-Sheet 4 Patented Dec. 12, 1933 UNITED! STATES PATENT OFFICE GINES Francis Marbnrg, Yonkers, N. Y. Application June 18, 1929. Serial No; 371,861

12 Claims.

My invention refers to improvements in internal combustion engines and particularly in primarycombustionor explosion-devices into which fuel is injected in form of spray by known methods, preferable by s'olidor airless-injection, and wherein fuel may be ignited by com pression. The object is to produce explosion or combustion within an outer portion or compartment of the primary chamberfwhile fuel vapors are injected into a relativelysmall pocket or inner compartment of the primary chamber which is arranged in permanently open communication with the cylinderor main-compressionor combustion-chamber and arranged substantially in series between the latter and the outer portion of the' primary chamber during the power stroke. The major portion of the fuel vapors cannot burn up withinthe primary chamber but is more or less vaporized, gasified, or broken up or atomized, while being forced to flow through the pocket and into the cyline der-or main-combustionchamber wherein it mixes with the main body of compressed air and burns up. The difiiculty heretofore has been to produce proper mixture and combustion within the outer, larger portion of the primary-chamber, in such manner, that the major or unburned portion of the fuel vapors is forced to flow sufficiently quickly from the pocket or fuel injection compartment into the cylinder-or maincombustion-chamber, but Without producing explosion or detonation within the latter. The method in which applicant is solving this question willbe fully understood after the action within his present device has been explained. The novel mechanical features, as illustrated, consist mainly in providing peculiarly arranged auxiliary air inlet ports and in the manner of interconnecting these ports with the pocket or fuel injection compartment and with outer portions of the primary chamber as well as with the cylinder-or main-compression-or combustion-chamber. The objects of applicants invention are, to permit a limited amount of auxiliary air to enter through auxiliary air-inletports or passages directly into the inner or fuel-injection compartment or pocket, aside of air entering therein through the atomizing ports or passages, and secondly, to simultaneously admit air through other auxiliary air-inlet ports or passages directly into the outer compartment of the primary chamber and to control the relative amounts of air supplyto theinner and outer compartments during compression and regulate the overpressure within the inner compartment (Cl. 123-:32) i or pocket and the amount of fuel vapors driven into the outer compartment before explosion takes place in the latter compartment.

Referring now to attached drawings, wherein same numbers refer to same parts,'Figs. 1 to 0" 6 show one embodiment of my invention. Fig.

1 is a vertical section within a plane through the axis of aprimary chamber, Figs. 2 and 3 are horizontal sections taken at vertical planes to the axis, respectively, on lines A B and C D of 5" Fig. 1. Figs. 4 and 5 respectively represent enlarged view and section through a valve shown and marked 21 in Fig. 1. Fig. 6 shows a bottom View of a deflector which is split and marked 26 in Fig. 1. I V 1 7 Figs. '7 to 9 show another illustration of my invention, Fig. "7 showing a section within a plane through the axis of the primary chamber, and Figs. 8 and 9 showing respectively a top view and side elevation of axially outer and inner portions of a tube and a deflector, marked respectively l2, l4; and 13 in Fig. 7.

Figs. 10 to 12 show still another design ofmy device, Fig. 10 being a section within a plane through the axis, Fig. 11 showing atop view with the cover or spray valve taken off and Fig. 12 showing a side view or elevation of a tube and deflector.

Referring now particularly to Figs. 1 to 3, 11 represents a wall enclosing or forming a primary-combustion-chamber, 10 may indicate a space containing cooling liquid, 12 may be a tube or member or partition, subdividing the primary chamber, preferably into a concentrically inner compartment marked 31, and a concentrically outer compartment marked 30. 13 may be a disk-shaped member or defiector, which may be a part or portion of the tube. The main purpose of the disk-shaped deflector consists in forming a narrow port 95 23 between the same and a cooled wall, the purpose of which will be explained later on. 14- may be a threaded extension of the tube or deflector, which we may callinner tube end and which may be screwed into the wall 11, the lower 0 or inner end of the extension having preferably a number of perforations or openings marked 15- solidor airless-injection fuel oil engines, fuel pumps and spray valves are universally used and any efiicient known type of fuel pump or spray valve may be used in connection with the device; this is not a part of the invention and therefore need not be shown. The spray valve casing may be ground tight to its seat in the wall and held down in known manner, not shown herein. The tube and spray valve casing may be so arranged in relation to each other that an annular or ringshaped space 18 remains between them, as shown, which forms the principle or main permanent communication between the radially inner and outer compartment.

19 are perforations within the outer portion of the tube or subdividing member which latterportion is surrounded concentrically by the outercompartment 30 and forming additional permanent communication between the inner and outer compartment. 29, as shown, are smaller perforations provided between the lowest portion of the outer compartment and the inner compartment or pocket, assuring that ,fuel under all circumstances is completelydrained from the outer compartment during each power stroke. 20, are perforations within the inner tube end, the purpose of which will be fully explained hereinafter. 25 are notches shown in the top of the tube for screwing in or unscrewing the latter by means of a wrench. deflector which preferably is compressed before being placed into the primary chamber, being semi-cooled at its radially outer surface by contact with the enclosing cooled wall. It gets hot and assists in breaking up or evaporating fuel and also assists in protecting a large portion of the spray valve against excessive heat which might otherwise cause gasifying within the spray valve casing or undue radial expansion of, the valve or cover as compared with the cool wall,

' fwhich must be avoided in order to keep a tight joint between valve casing and wall. 28 is a ring which, as shown, may be screwed on the tube, being kept hot by the latter and acting as a hot deflector as will be explained later on.

It is preferably semi-heat-insulated from'the enclosing cooled wall, by a small space, as shown,

marked 32. p

The port 23 has an enlarged portion adjacent the perforations 20, as illustrated, formed by the hot ring-shaped member 28 and by'the hot extension 14 of the partition number 12, the purpose of which will also be explained later on. 21 is a ring-shaped valve, of large diameter, arranged concentrically around the inner com- 4 and 5, because it is an important feature of the invention. It will be seen, that rests 21a and 21b are provided at the axially outer and inner side of the valve, in such manner, that gasor 1 air-pressures may instantly act substantially at its entire outer and inner surfaces, as will be better understood later on. Port 22, annular port 24, valve 21, port 23 and perforations 20, are arranged in such manner, thatduring compression, air may flow from the main compression, or combustion-chamber, through the valve, directly into the inner compartment 31 of the primary chamber, while an annular port 2'7 is arranged in such manner, that air may simultaneously flow through the valve and port 27 directly into the outer compartment of the primary chamber. It will be understood, that the valve opens automatically, as soonas the pressure within the main chamber becomes higher 26 may bea split or flexible,

than within the primary chamber and that it closes quickly automatically, as soon as the pressure within the primary chamber, as a result of combustion within the outer compartment, becomes higher than within the main combustion chamber.

During compression, the inner compartment may or may not be arranged substantially in series between the outer compartment and the main combustion chamber, because air flows from the main combustion chamber simultaneously directly into the outer and inner compartments, but during the power stroke, during the fuel-scavenging period, the inner compartment must be arranged substantially in series between the outer compartment and the main combustion chamber, for reasons which will be fully explained later on. The relative amounts of air flowing simultaneously into the inner and outer compartment, should be so proportioned, that a predetermined amount of fuel-air mixture is driven at a predetermined velocity, from the inner into the outer compartment, in order to produce perfect combustion within the latter compartment during a time period corresponding to a given angular turn of the crankshaft, thus permitting all fuel to be injected, before the explosion or combustion within the outer compartment has spent its main initial force, as will be explained more fully later on.

As seen from Figs. 1 and 3, the annular port 23 is widenedout or enlarged at the place where it joins with perforations 20, thus forming a small chamber between the hot member 28 and the hot tubular member. The object of this slightly enlarged annular port space, is, to produce slight explosion or combustion therein, the instant fuel vapors flow from the inner compartment through perforations20, into port 23, as a result of the explosion or combustion within the outer compartment, before the valve is completely closed. within this slightly enlarged annular space of the port 23, accelerates closing of the valve and at the same instant prevents additional fuel vapors from entering into the port 23 from the.

inner compartment. The hot deflector 28 assists inproducing the explosion, which is of great importance, first, in order to prevent fuel from reaching the valve or vvalve seat (where it would form carbon deposits, whichwould make the valve quickly inoperative because of its extremely small lift) and furthermore, in order to avoid so-called dead or semi-dead fuel spaces.

It will be understood, that, because of the gir large outer and inner'diarneter of the ringshaped valve and its corresponding large radially outer and inner valve area, the valve may operate with extremely small lift, which is essential, because the valve must close and open very f4 quickly, and because, on account of the high temperatures, no springs can be used in connection with the valve. Applicant proposes to use only .02", more or less, valve lift, in order to avoid undue wear and tear of the valve and in order to assure very'quick closing, with as little back flow of compressed air or gases througlrthe a valve, into the main compression, or combustionchamber, as possible.

The peculiar design of the valve permits in.- coming air, which passes through the ports 22 of the cooled wall, to slightly cool the valve.

Because valve rests are provided, as illustrated and near the radially inner and outer portions of the valve, the respectiveair and gas pressures are acting instantly, substantially on the entire axially outer and inner valve surfaces, this further assists in producing very quick opening and closing. In connection herewith, it is immaterial, whether these rests are arranged on the valve itself 'or on the respective outer or inner valve seat.

The peculiar intermittent communication, provided between the outer and inner compartments of the primary chamber and the main combustion chamber, by means of the above said valve-controlled ports or passages, constitutes the main feature of the invention and its object will be explained later on, in connection with the description of the action of the device.

. Figs. 7 to 9 difier from Figs. 1 to 3 in one essential point, because the deflector 13 in Figs. '7 to 9 has spiral; blades which produce spiral or rotary motion of compressed air while passing from the valve through port 27 into the outer portion of the primary chamber, the purpose of which will lateron be explained. It will furthermore be seen, that the deflector 26, as shown herein, may be a part or portion of the valve-casing being only partly separated from the latter by an annular groove, in such manner, that it is partly semi-heat-insulated from the rest of the valve casing, therefore becoming sufficiently hot to act as fuel-evaporator, while the valve-casing is partly protected against excessive heat of combustion, similarly as explained hereinbefore.

Figs. 10 to 12 show a device which is similar to the device shown in Figs. '7 to 9, except that the axially outer tube end is left off. It has been found that with certain cheap fuels the perforations 19 are apt to clog up and the device in such cases may be used without the axially outer tube end, as shown.

The action within my present device is similar as explained in my United States Patent No. 1,700,903, dated February 5th, 1929, and applicant refers to the device shown and described therein.

The basic action will now be more fully explained in order to clearly define the purpose of my present invention and to show wherein the action within the present device differs essentially from the action within my previously patented and other similar known devices.

Broadly speaking, the main object of similar devices consists in producing proper pulsations, if this expression may be permitted, within the primary chamber. A small portion of the total compressed air is forced to flow during compression from the cylinderor main-compression, or combustion-chamber into the primary-chamber and a mixture of gas and broken up fuel is forced to flow from the latter back into the cylinder vor main-combustion-chamber, in such manner,

that fuel which is injected into a pocket or injection compartment of the primary-chamber, is more or less vaporized and broken up and'a greatlyoversaturated relatively cool slowly burning mixture results within the pocket, which must first be driven, by an explosion produced within an outer or explosion compartment, into the cylinder or main-combustion-chamber, before it can burn up completely as fast as it mixes with the main body of compressed air contained within the cylinderor main-combustion-chamber.

The motor may be started by producing high compression and ignition by turning it over sufiiciently quickly by means of auxiliary starting motor, in known manner, and if desired any known starting device'm'ay in addition be used for getting the first explosions, after which ignition is very reliable, provided compression of 500 to 600 lbs., more or less per square inch, is used. Starting devices are universally used and have not been shown herein because they do not refer to the invention.

In order to clearly understand the invention, it should be understood for the sake of illustration, that the primary-chamber may receive from the cylinder-or main-combustion-chamber from 15 to 20%, more or less, of the total compressed air, while 80 to 85%, more or less, of the total compressed air, may remain within the cylinderor main-combustion chamber, during maximum compression. The tube or radially inner com partment or pocket of the primary-chamber, may contain from 10 to 25%, more or less, of the total amount of compressed air within the primarychamber or from 2 to 5%, more or less, of the total amount of air which. is compressed within the cylinder. If fuel is injected into the tube or pocket, within the tu e instantly becomes very much oversaturated and very limited or greatly suppressed slow combustion takes place within the tube, or pocket, instead of an explosion, asgenerally wrongly presumed. Injection may start 10 to 15, more or less, ahead of dead center.

crank position and may continue about until dead center position has been reached. The spray may form an angle of to 93 more or less, as indicated by fine lines. The smaller or finer globules of the vapor penetrate less deeply into the onrushing dense air and may remain within the outer end of the tube or pocket or be carried partly through port 18 into the concentrically outer compartment of the primary chamber,

while the larger drops or globules are thrown violently against the hot tube and are broken up into a large number of smaller globules, which penetrate more or less deeply, into the tube. On account of the low temperature of the relatively very large amount of injected fuel and the great amount of latent heat consumed in evaporation, the temperature within the major portion of the tube and within the furthest outer end of the primary-chamber is momentarily lowered instead of being raised, thus delaying combustion and permitting accumulation of greatly oversaturated mixture within the tube and within the furthest outer end of the concentrically outer compartment. Meanwhile compressed air continues to rush into the primary chamber and forces a limited amount of the finest fuel vapors to flow through perforations 19 into the outer compartment, wherein it mixes with a relatively large quantity of compressed air and burns up and successively produces fuel scavenging, and combustion within the cylinder.

Good results can only be produced with small perforations or atomizing ports '15 within the axially inner tube end. If larger perforations 15 are used, fuel vapors evidently are quickly forced into the outer compartment, producing quick combustion therein and quick but incomplete discharge of fuel into the cylinder, or main-combustion-chamber and as a result a portion of the fuel which is injected late, drains gradually and late into the cylinder or inain-combustion-chamber during the middle or later portion of the power stroke, or pie-explosion within the primary-chamber may produce a series of explosions successively and with great regularity within the primary chamber as well as within the cylinder, or main-combustion-chamber, during each and as in applicants device, the mixture every power stroke. Again, if the perforations 15 are, made smaller, the engine operates smoothly, but fuel discharge into the cylinder, and combustion within the cylinder, are late, evidently because combustion within the outer compartment is insufficient to produce proper scavenging and because the more uniform back-pressure, resulting from smaller perforations, produces a more steady but slower discharge of fuel into the cylinder, or main-combustion-chamber.

.Numerous tests with carefully taken indicator diagrams, which applicant .made during many years, with many sizes and types of motors having similar devices, with perforations 15 in the inner tube end varying considerably, prove the above statements. With normal sizes of perforations 15 and water-cooled walls of the primary chamber, the engine operates smoothly, but combustion within the cylinder is more or less late. Changingthe timing of injection has slight influence, on the contrary, combustion within the cylinder, or main-combustion-chamber remains practically unchanged while advancing or retarding injection several degrees.

A compromise had to be made, making these perforations 15 sufiiciently large to permit sufficient compressed air to flow into the primary chamber at usual motor speed and for the fuel mixture to flow into the cylinder, or main-com bustion-chamber, within a proper time period,

with however a considerable sacrifice of energy. The perforations 15 were made as large as compatible with smooth operation of the motor, but more or less late scavenging, andlate combustion took place within the cylinder.

Applicant shows herein a novel way of controlling the flow of fuel or mixture from the tube into the outer compartment, or of controlling the quantity of fuel-air mixture flowing into the outer portion of the primary chamber, by admitting compressed air through one group of valve-controlled air-inlet ports or passages 22, 24, 27, which terminate directly into the outer compartment or outer portions of the primary chamber, whereby pressure within the compartments becomes more or less equalized. Applicant realized that a certain amount of fuel vapors must be forced to flow very quickly into primary chamber, just ahead of dead center crank position, but that this amount should be properly regulated. Actual tests proved, as stated hereinbefore that it is not advisable to enlarge the'perforations 15, because this would permit fuel to flow too quickly from the primary chamber into the cylinder, or main-combustion-chamber, causing more or less explosion or detonation within the latter, which must be avoided. On the contrary, smaller perforations 15 than have been used heretofore, are preferable. For this reason a certain amount of compressed air, as shown, is simultaneously permitted to enter into the inner end of the tube or pocket through the valve-controlled air inlet ports or another group of valve-controlled airinlet ports or perforations 22, 24, 23, 20, besides the air entering through perforations 15, By properly proportioning port 2'1 as well as port 23 and perforations 20 and the atomizing DOrts 15, the respective volumes of air flowing directly to the inner or fuel-injection compartment and simultaneously, directly into the outer compartment, may be accurately regulated and con-' trolled, because a predetermined overpressure .may be produced within the fuel-injection com;

between the outerend of the inner compartment and the outer compartment, small overpressure is produced within the inner compartment as compared with the outer compartment during beginning of fuel-injection, but on account of the larger ports, evidently approximately the same amount of fuel vapor flows into the outer compartment during the same time period, within certain limits, producing therein about the same combustion results as before, as proven by tests.

It should also be understood, that with increasing motor speed, the overpressures within the inner compartment, over and above the pressures within the outer compartment, increase within similar known devices, but experience proves, that these greater overpressures are required at higher motor s eed, in order to accellerate the flow of fuel-air mixture sufficiently, to quicken or intensify combustion within the outer compartment to such a degree-that the inner compartment becomes completely fuel scavenged during about the same angular turn or the crankshaft, with the r it of simultaneously greatly improved atom ation and itensified combustion wit sin combustion chamber. For these reasons, siin ar known devices operate well with greatly varying motor speeds. Applicants purpose, as explained, consists mainly in affecting more complete combustion during beginning of the power stroke, while the flexibility and smooth operation of the motor remains the same as heretofore. 7

To make matters still clearer, the total time period of comb ion within the outer compartment is about in,e1'sely proportional to the motor speed. In other words, the total time period of combustion decreases, with increasing motor speed, because the intensity of combustion within the outer compartment increases about in the same proportionas the motor speed, within certain limits, causing qu' ker fuel-scavenging and quicker com ion within the main combustion chamber, with incr ing motor speed. Applicants invention, the ore explained, regulates the overpressure produced within the inner compartment, which in turn regulates or determines the speed, with which fuel is driven into the outer compartment, thus determining the total timeand intensity cf combustion Within the primary as well as within the main combustion chamber. a I

It should be undrstood, that the total capacity of. the enlargement of port 23 should be much less than the total capacity of the outer compartment, the obiect of the enlargement consisting solely in producing sufficient ccznbustion or explosion therein and sufficient overpressure above the valve, to close the latter quickly, thus preventing additional fuel from entering into port 23. Large capacity of this enlarged port would constitute a great loss of pewcr and excessive combustion "within the port 23 obviously would not assist fuelscavenging, which must be produced only by'an effective explosion within the outer compartment. Air must as much as possible, remain within the main combustion chamber where the power is generated.

Motors operating normally at moderate speed, require relatively small total cross-sectional area of auxiliary air-inlet ports at their termination into the inner compartment, as compared with the total cross-sectional area of the auxiliary air-inlet ports terminating directly into the outer compartment, while motors operating at normally high speed, require relatively greater total cross-sectional area of the auxiliary air-inlet ports at their termination into the inner compartment, in order to produce quick and intense combustion within the outer compartment, as explainedhereinbefore and in order to reduce the loss of energy required to force a sufficient quantity of air and fuel through the inner into the outer compartment, during the short time periods provided therefore. Applicant does not believe that direct auxiliary air-inlet into the outer compartment is under all circumstances necessary and he broadly claims auxiliary air-inlet directly into the inner compartment, under clearly defined conditions. o

By using small perforations 20 and a hot conductor 28, only a small amount of fuel air mixture, can during beginning of explosion within the outer compartment, momentary flow from the inner compartment through perforations 20 into the port 23, and by impinging on the hot conductor, breaks up or evaporates and burns or explodes as soon as it enters into the auxiliary port. As soon as the valve closes on %count of combustion within the outer compartment and within port 23 and on account of the increased pressure produced thereby above or at the outer side of the valve, port 23 communicates directly with port 27, causing gases to flow from the outer com-v partment, through ports 27 and 23 and through perforations 20 into the inner compartment, thus cleaning the top of the valve and fuel-scavenging the port 23 during each power stroke. This is very important for the proper operation of the valve, because of the exceedingly small valve-motion. From these latter explanations it becomes also clear, that the total area of the perforations 20 should not be greater than just required to accomplishthe necessary objects described hereinbefore.v Applicant ordinarily prefers a total cross-sectional area of auxiliary ports at or near their termination into the inner compartment of approximately the same as that of the atomizing ports, but conditions'may vary greatly. He claims a total cross-sectional area of the auxiliary ports at or near their termination into the inner compartment of less than that of the total crosssectional area of the ports provided between the outer end portion of the inner compartment and the outer compartment.

It is evident, that with applicants device somewhat smaller perforations 15 or a smaller total area of the atomizing ports can and should be employed than permissible heretofore, thus providing more time for fuel-injection before the main initial explosive force within the primary chamber has been spent in scavenging, because the back pressure within the inner compartment, over and above the pressure within the main combustion chamber, rises'higher, and becomes more uniformly high, thereby improving atomizing, all of which is of importance, especially at high motor speed, because the fuel must all be injected during about 10 to 15 turn of the crankshaft, at very high fuel-injectionpressures, and because fuel-injection during less turn of the crank, would become practically very diflicult or impossible within required ranges of motor speeds, especially for aeroplanes and automobiles.

A novelly arranged spiral deflector is preferably provided between the tubular partition member and the cooled wall, in such manner, that air flowing directly into the outer compartment, receives spiral or rotary motion and continues to revolve in the same direction while combustion takes place within the latter compartment, thereby producing perfect fuel-air mixture of substantially uniform relatively low temperature and slightly suppressed explosion or combustion.

As illustrated, compressed air is conducted from the cylinder or main compression, or combustion-chamber through valve-controlled airinlet ports, because this is simple and because air flowing through the valve and ports or passages, must be timed and properly proportioned with the air flowing through the permanently open atomizing ports, but the invention is not limited to the design shown-herein.

It will be understood, that during the power stroke the inner compartment or pocket is placed substantially in series between the outer compartment and the main combustion chamber and that substantially all gases are forced to flow from the outer compartment through the major portion of the inner compartment or pocket into the main combustion chamber, thus avoiding so-called dead fuel spaces, while during compression, the inner compartment or pocket may be arranged more or less parallel with the outer compartment, depending on the relative amounts of air, which flows from the main combustion chamber simultaneously directly into the outer as well as inner compartment or pocket.

The expression, that the inner compartment, during the power stroke, is arranged in series",

as stated in the claims, means, that, during beginning of the power stroke, explosionor combustion-gases flow from the outer compartment, mainly into theouter end portion of the inner compartment and through the latter into the main combustion chamber, which is accomplished by arranging the main ports or passages of communication between the compartments, at the outer end of the inner compartment, and by placing the fuel-atomizing ports or passages at the inner and of the inner compartment, in such manner, that so-called dead fuel-spaces are substantially avoided in connection with the inner compartment as well as within the auxiliary valve-controlled air-inlet ports or passages during the fuel-scavenging period, and that the greater portion of the injected fuel-vapors are forced to flow into the main combustion chamber, substantially ahead of the explosion, or combustion-gases of the outer compartment.

Ihe expression inner compartment means the compartment in closest communication with the main combustion-chamber duringthe power stroke, while the outer compartment communi cates with the main combustion-chamber, during the power stroke, mainly by passage through the inner compartment. Similarly the expression inner end portion of the inner compartment, means the portion which is in closest communication with the main combustionchamber, while the outer end portion of the a Vice.

inner compartment communicates also with the main combustion-chamber, only by passage through the inner end portion of the, inner compartment, during the power stroke. Fuelscavenging means the driving of fuel-vapors from the inner or fuel-injection compartment into the main combustion-chamber.

. The expression Diesel type of engine, means that the air--temperature, as a result of high compression, ignites fuel entering into the main combustion-chamber, without ignition device within the latter chamber. An ignition device within the primary combustion-chamber, for starting the engine, has not been shown, because such ignition devices have nothing whatever to do with the invention, and any known ignition device may be used within the latter chamber.

Approximate relative capacities of the maincombustion-chamber and primary-combustionchamber and fuel receiving pockets, during max: imum compression, such as mentioned hereinbefore for the sake of illustration, produce good results, but Ido not limit myself to such relative capacities because good resultshave been ob- V tained with similar devices'having greatly varying relative capacities of these chambers an fuel receiving pocket. I

Water-cooled walls for primary chambers, heretofore, as explained, have been preferable to air-cooled walls, in connection with Dieselengines for which this device is especially adapted,

but any known efficient cooling system may be used for cooling the wall of the primary chamber and my invention is not restricted to any .particular cooling system.

The device is not limited in its use to any type of motor, and any fuel which may be sprayed into a primary combustion chamber in known manner and which burns quickly in highly compressed air may be used with applicants de- From the aforesaid it is evident, that my pres: ent device improves thermal efficiency andfueleconomy and increases maximum permissible speed and horsepower of themotor,

Various modifications may be made in the invention without departing from the spirit thereof and the present exemplifications are to be taken as illustrative and not limitative thereof.

I claim:

1. In an internal combustion engine substantially of the Diesel type, a main combustion cham ber, a primary combustion chamber consisting of a large outer compartment and a smaller inner fuel-injection compartment'or pocket arranged,

substantially in series between said outer compartment and said main combustion chamber during the power stroke, in such manner, that socalled dead fuel spaces are substantially avoided within said inner compartment or pocket during fuel-scavenging, means spraying a fuel-charge said inner compartment or pocket and said outerv compartment andone or more atomizing passages of relatively small total cross-sectional area provided between the inner portions of said inner compartment or pocket andsaid main combustion chamber, a group of auxiliary air-inlet passages starting from said main combustion chamber'and terminating directly into said inner compertinent or pocket, a valve controlling said group of auxiliary passages, said valve opening and clos ing said auxiliary passages automatically whenever pressure within said main combustion chamber becomes greater or lesser respectively than within portions of said primary combustion chamber, the total cross-sectional area of said auxiliary passages'at or near their said termination into said inner compartment or pocket being less than the total cross-sectional area of said passage or passages provided between said outer portions of said inner compartment or pocket and said outerv compartment.

,2. In an internal combustion engine substanially of the Diesel type, a main combustion chamber, a primary combustion chamber consisting of a large outer compartment and a smaller inner fuel-injection compartment or pocket arranged substantially in series between said outer compartment and said main combustion chamber during the power stroke, in such manner, that so-called dead fuel spaces are substantially avoided within saidinner compartment or pocket during fuel-scavenging, means spraying a fuelcharge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one or more permanently open passages of relatively large total cross-sectional area provided between outer portions of said inner compartment or pocket and said outer compartment and one or more atomizing passages of relatively small total cross-sectionalarea provided between the inner portions of said inner compartment or pocket and said main combustion chamber, one or more auxiliary air-inlet passages starting from said main combustion chamber and terminating directly into said inner compartment or pocket, a valve controlling said auxiliary passage, or passages, said valve opening and closing said auxiliary passage or passages automatically whenever pressure within said main combustion chamber becomes greater or lesser respectively than within portions of said primary combustion chamber por-' tions of said auxiliary passage or passagesbeing arranged directly, between said valve and said inner compartment or pocket, the total capacity of said latter portions having less than the total capacity of said outer compartment, and the total cross-sectional area of said auxiliary passage or passages at or near their said termination into said inner compartment or pocket being less than the total cross-sectional area of said passage or passages provided between said outer portions of said inner compartment or pocket and said outer compartment.

3. In an internal combustion engine substantially of the Diesel type, a main combustion chamber, a primary combustion chamber consisting of a large outer compartment and a smaller inner fuel-injection compartment or pocket arranged substantially in series between said outer compartment and said main combustion chamber during the power stroke, in such manner, that so-called dead fuel spaces are substantially avoided within said inner compartment or pocket during fuel scavenging, means spraying a fuel-charge for aid chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one or more permanently open passages of relatively large total cross-sectional area provided between outer portions of said inner compartment or pocket and said outer compartment and one or more atomizing passages of relatively small total cross-sectional area provided between inner portions of said inner compartment or pocketand said main combustion chamber, a group of auxiliary air-inlet passages starting from said main combustion chamber and terminating directly into said inner compartment or pocket, a valve controlling said group of auxiliary passages and opening and closing said auxiliary passages automatically whenever pressure within main combustion chamber becomes greater or lesser respectively than within portions of said primary combustion chamber, the total cross-sectional area of said auxiliary passages at or near their said termination into said inner compartment or pocket being less than the total cross-sectional area of said passage or passages provided between said outer portions of said inner compartment or pocket and said outer compartment, said valve being ring-shaped and arranged substantially concentrically around said inner-compartment or pocket, valve-rests being provided adjacent the axially outer and inner surfacs of said valve, in such manner, that the respective gasor airpressures are acting instantly substantially at the entire axially outer and inner surfaces of said valve, thus closing and opening said valve quickly.

4. In an internal combustion engine substan tially of the Diesel type, a main combustion chamber, a primary combustion chamber consisting of a large outer compartment and arsmaller inner fuel-injection compartment or pocket arranged substantially in series between said outer compartment and said main combustion chamber during the power stroke in such manner, that socalled dead fuel spaces are substantially avoided within said inner compartment or pocket during fuel-scavenging, means spraying a' fuel-charge for said chambers into said inner cornpartmentv or pocket shortly before or substantially during maximum compression, one or more permanently open'passages of relatively large total cross-sectional area provided between outer end portions of said inner compartment or pocket and said outer compartment and one or more atomizing passages of relatively small total cross-sectional area provided between inner portions of said inner compartment or pocket and said main combustion chamber, a group of auxiliary air-inlet passages starting from said main combustion chamber and terminating directly into said inner compartment or pocket, a valve controlling said group of auxiliary passages said valve opening and closing said auxiliary passages automatically when ever pressure within said main combustion chamber becomes greater or lesser respectively than within said primary combustion chamber,- the total cross-sectional area of said auxiliary passages at or near their said termination into said inner compartment or pocket being less than the total cross-sectional area of said passage or passages provided between said outer portion of said inner compartment or pocket and said outer compartment, a hot deflector being arranged within a portion of said auxiliary passage between said valve and said inner compartment or pocket, in such manner, that fuel entering into said latter portion of said auxiliary passage from said inner compartment or pocket during beginning of combustion or explosion w fiin said outer co-.. partment, before said valve is closed, impinges against said hot deflector and evaporates or breaks up and burns or explodes, said deflector being kept hot by contact with hot parts and by being substantially heat-insulated from cooled parts.

,5; In an internal combustion engine substantially of the Diesel type, a main combustion chamber, a primary combustion chamber consisting of a large outer compartment and a smaller inner fuel-injection compartment or pocket arranged substantially in series between said outer compartment and said main combustion chamber during the power stroke, in such manner, that so-called dead fuel spaces are substantially avoided within said inner compartment or pocket during fuel-scavenging, means spraying a fuelcharge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one or more permanently open passages of relatively large total cross-sectional area provided between outer portions of said inner compartment or pocket and said outer compartment and one or more atomizing passages of relatively small total cross-sectional area provided between inner portions of said inner compartment or pocket and said main combustion chamber, a group of auxiliary air-inlet passages starting from said main combustion chamber and terminating directly into said inner compartment or pocket, a valve controlling said group of auxiliary passages opening and closing said auxiliary passages automatically whenever pressure within said main combustion chamber becomes greater or lesser respectively than within said portions of said primary combustion chamber, a portion of said auxiliary air-inlet passages leading from said valve to said inner compartment or pocket, being enlarged to a small'chamber, which latter communicates with said inner compartment or pocket through one or more passages or perforations of smaller total cross-sectional area than said total cross sectional area of said passage or passages provided between said outer portion of said inner compartment or pocket and said outer compartment.

6. In an internal combustion engine substantially of the Diesel type, a main combustion chamber, a primary combustion chamber consisting of a large outer compartment and a small inner fuel-injection compartment or pocket arranged substantially in series between said outer compartment and said main combustion chamber during the power stroke, in such manner, that socalled dead fuel-spaces are substantially avoided within said inner compartment or packet during fuel-scavenging, means spraying a fuel-charge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one or more permanently open passages of relatively large total crosssectional area being provided between outer portions of said inner compartment or pocket and said outer compartment, one or more permanently open fuel-atomizing passages of relatively small total cross-sectional area being provided between the inner portions of said inner compartment and said main combustion chamber, a group of auxiliary air-inlet passages starting from said main combustion chamber and branching off directly into said inner and said outer compartments of said primary combustion chamber, a valve controlling said auxiliary air-inlet passages at the point of junction of said branches, saidvalve automatically opening and closing said auxiliary passages whenever pressure within said main combustion chamber becomes greater or lesser respectively than within said primary combustion chamber.

7. In an internal combustion engine substantially of the Diesel type, a main combustion chamber, a primary. combustionchamber consisting of a' large outer compartment and a small inner fuel-injection compartment or pocket arranged substantially in series between said outer compartment and said main combustion chamber during the power stroke, in such manner, that so-called dead fuel-spaces are substantially avoided Within said inner compartment or pocket during fuel-scavenging, means spray ing a fuel-charge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one or more permanently open passages of relatively large total cross-sectional area being provided between outer portions of said inner compartment or pocket and said outer compartment, one or more permanently open fuel-atoinizing passages of relatively small total cross-sectional area being provided between inner portions of said inner compartment and said main combustion chamber, a group of auxiliary air-inlet passages starting from said main combustion chamber and branching off directly into said inner and said outer compartments of said primary combustion chamber, a valve controlling said auxiliaryair-inlet passages at the point of Junction of said branches, said valve automatically opening and closing said auxiliary passages whenever pressure within said main combustion chamber becomes greater or lesser respectively than within said primary combustion chamber, said valve and said groups of auxiliary passages being so arranged in relation to each other, that after said valve is closed, a small portion of the gases must flow from said outer compartment over said valve and through portions of said auxiliary passages terminating into said inner compartment or pocket, thus cleaning the top of said-valve and fuel-scavenging saidlatter portions of said passages.

8. In an internal combustion engine substantially of the Diesel type, a main compression or combustion chamber, a primary combustion chamber consisting of a large outer compartment and a small inner fuel-injection compartment or pocket which latter is arranged in permanently open communication with said outer compartment and said maincombustion chamber and substantially in series between the same during the power stroke, means spraying a fuel-charge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, auxiliary air-inlet passages being provided and arranged in such mannor that during compression, air is admitted through said auxiliary passages simultaneously directly into said inner compartment or pocket and directly into said outer compartment, a valve automatically opening and closing'saicl auxiliary passages, whenever the pressure within said main combustion chamber becomes higher or lower respectively than within said compartments, said auxiliary passages branching out 1 from said valve, said branches and said valve being so arranged that as soon as said valve is closed and during the continuation of the power stroke, gases flow from said outer compartment through said branches into said inner compartment, thus fuel-scavenging said branches.

9. In an internal combustion engine substantially of the Diesel type, a main combustion chamber, a primary combustion chamber consisting of a large outer compartment and a small inner fuel-injection compartment or pocket which latter is arranged in permanently open communication with said outer compartment and said main combustion chamber and substantially in series between the same during the power stroke, means spraying a fuel-charge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one group of auxiliary air-inlet passages terminating directly into said inner compartment or pocket, another group of auxiliary air-inlet passages terminating directly into said outer compartment, said groups of auxiliary passages being valve-controlled in such manner, that during compression air may flow through said auxiliary passages simultaneously directly into said inner and outer compartments and that said auxiliary passages are closed automatically as soon as combustion or explosion takes place within said outer compartment.

, 10. In an internal combustion engine substantially of the Diesel type, a main compression, or combustion-chamber, a primary combustionchamber consisting of a large outer compartment and a small inner compartment or pocket arranged in permanently open communication with and substantially in series between said outer compartment and said main compressionor combustion-chamber during the power stroke, means spraying a fuel-charge for said chambers into said inner compartment or pocket shortly before or substantially during maximum compression, one or more auxiliary air-inlet-passages terminating directly into said inner compartment or pocket, one or more auxiliary air-inletpassages terminating directly into said outer compartment, said auxiliary passages being valve-controlled, in such manner, that during compression air may flow through said respective auxiliary passages directly into each of said compartments, said auxiliary passages being closed automatically shortly before or about during maximum compression.

11. In'an internal combustion engine substantially of the Diesel type, a main compression, or combustion-chamber, a primary combustionchamber consisting of a large outer compartment and a small inner compartment or pocketarranged in permanently open communication with and substantially in series between said outer compartment and said main compressionor combustion-chamber during the power stroke,

means spraying a fuel-charge for said chambers.

into said inner compartment or pocket shortly before or substantially during maximum compression, one or more auxiliary air-inlet-passages terminating directly into said inner compartment or pocket, one or more auxiliary air-inlet-passages terminating directly into said outer compartment, said auxiliary air-inlet-passages being valve-controlled, in such manner, that during compression air may flow through said respective auxiliary passages directly into each of said compartments, said auxiliary passages being closed automatically shortly before or about during maximum compression, a spiral deflector being arranged at or near the place of said termination of said auxiliary air-passages intosa-id outer compartment.

.12. In aninternal combustion engine substantially of the Diesel type, a main compressionor combustion-chamber, a primary combustionchamber consisting of a large outer compartment and a small inner, compartment or pocket arranged in permanently open communication with and substantially in series between said outer compartment and said main combustion chamber during the power stroke, one or more'passages o1 relatively large total area being provided between outer portions of said inner compartment or pocket and said outer compartment and one or more atomizing passages of relatively'small total cross-sectional area being provided between inner portions of said inner compartment or pocket and said main combustion-chamber, one or more auxiliary air-inlet passages terminating directly into said inner compartment or pocket substantially between the said passages provided between said outer portions of said inner compartment or pocket and said outer compartment and the said atomizing passages, the total area of said auxiliary passage or passages at or near their said termination into said inner compartment being less than the total area 01' said passage or passages provided between said outer portions of said inner compartment and said outer compartment, means spraying a fuel charge for said chambers into said inner compartment shortly before or substantially during maximum compression, said auxiliary passage or passages being valve controlled, in such manner, that auxiliary air may enter through said auxiliary passage or passages directly into said inner compartment or pocket during compression and that said auxiliary air is out off automatically as soon as combustion or explosion takes place within said outer compartment. 7

FRANCIS MARBURG. 

